Fusinite liquefaction

Fusinite macerals are generally held to be inert in coking, and in liquefaction, as will be seen below. In the production of metallurgical coke, they do not become fluid on heating, and... 

For American and European coking coals the behaviour of semi-fusinite is generally less important since only small quantities of this maceral are usually present. However, South African coal used in coke oven-blends contains as little as 40 per cent vitrinite and as much as 45 per cent reactive semi-fusinite (12). The partial reactivity of the semi-fusinite fraction during liquefaction of Australian coals has been reported by Guyot et al (13). They found that the low reflecting inertinite in two coals up to (a reflectance from 1.40 to 1.49) was reactive. This agrees with the results of Smith and Steyn (12) who consider that the semi-fusinite fraction in South African coals up to V- 5 (1.50 - 1.59) can be reactive to coking. 

Liquefaction of inertinites is not always as poor as the name would imply. Table III shows some conversion data taken from Ref. (91), where conversion is defined as ethyl acetate solubles plus gases. The low reflecting Australian fusinites and seini-fusinites are reactive compared to the Illinois samples. This has been confirmed by a recent study on Australian inertinites (93) where it has been found that at higher temperatures (450 C) up to 54% of the inertinite was calculated to be converted. This difference between the Australian and North American inertinites has also been observed in carbonization reactions (94). 

On the other hand, fusinite offers some resistance to the low-temperature hydrogenation process, which may not be surprising considering the nature of this particular maceral (Chapter 4). And, microscopic examination of residual material (often referred to incorrectly as unconverted material) from coal liquefaction has indicated structures characteristic of fusinite thereby offering further evidence for the comparatively low reactivity of this maceral. 

Another aspect of coal behavior in relation to liquefaction that has also received (and is stiU receiving) some attention is the relationship of liquid yield to petrographic composition (Chapter 4) (Gagarin and Krichko, 1992). For example, vitrinite can be converted to liquid products readily as can exinite, but fusinite is quite resistant to liquefaction conditions and, thus, the petrographic composition of coals (whatever the rank) may be an important variable in determining the yields of liquid products. 

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